Periodic maintenance an d a djustment
7-3
7
10 *Rotor nut
(flywheel magneto) Tighten.
11 *
Kickstarter system Check idle gear for damage. Replace if necessary.
Check exhaust pipe and muffler for
carbon deposits.
12 *Exhaust system
Clean.
Check crankshaft for carbon depositsand damage.13 *Crankshaft
Clean.
14 *
Carburetor Check carburetor settings and for
obstructions.
Adjust and clean. Check condition.
15Spark plug Clean and regap.
Replace.
Check chain slack, alignment and
condition.
16 *Drive chain Adjust and thoroughly lubricate chain
with Yamaha chain and cable lube or
equivalent.
Replace.
NO. ITEM ROUTINE
After
break-in
Everyrace
Every
third race
Every
fifth race
As
required
7 *Clutch Check clutch housing, friction plates,
clutch plates and clutch springs for
wear or damage.
Adjust.
Replace.
8 *
Transmission Change the transmission oil. Check transmission for damage. Replace bearings.
9 *Shift forks, guide
bars, shift cam Check all parts for wear and damage. Replace if necessary.
UB4B80E0.book Page 3 Tuesday, March 27, 2018 1:39 PM
Periodic maintenance an d a djustment
7-8
7
6. Refill with the specified amount of
the recommended transmission
oil.
NOTICE
ECA10453
In or der to prevent clutch slip-
pa ge (since the transmission oil
also lu bricates the clutch), do
not mix any chemical additives.
Do not use oils with a diesel
specification of “CD” or oils of a
hi gher quality than specifie d. In
a ddition, do not use oils la bele d
“ENERGY CONSERVING II” or
hi gher.
Make sure that no forei gn mate-
rial enters the transmission.
7. Check the O-ring for damage, and replace it if necessary.
8. Install and tighten the transmis- sion oil filler cap and its O-ring.
9. Start the engine, and then let it idle for several minutes while checking
it for oil leakage. If oil is leaking,
immediately turn the engine off
and check for the cause.
EAU20071
Coolant
The coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUM1296To check the coolant level1. Place the vehicle on a level surfa- ce and hold it in an upright posi-
tion.
TIP
The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.
2. Remove the radiator cap and
check the coolant level in the radi-
ator. WARNING! Never attempt
to remove the ra diator cap
when the en gine is hot.
[EWA10382]
Ti ghtening torque:
Transmission oil drain bolt: 10 N·m (1.0 kgf·m, 7.4 lb·ft)
Recommen ded transmission oil:
Motor oil SAE 10W-30 type SE or
higher or Gear oil SAE 85W GL-3
Oil chan ge quantity:
0.50 L (0.53 US qt, 0.44 Imp.qt)
1. Radiator cap
1
UB4B80E0.book Page 8 Tuesday, March 27, 2018 1:39 PM
Periodic maintenance an d a djustment
7-17
7
EAU65775
A djustin g the clutch lever free
play
Measure the clutch lever free play as
shown.
Periodically check the clutch lever free
play and, if necessary, adjust it.
To increase the clutch lever free play,
turn the clutch lever free play adjuster
in direction (a). To decrease the clutch
lever free play, turn the adjuster in di-
rection (b).
TIP
If the specified clutch lever free play
cannot be obtained as described
above, proceed as follows.
1. Fully turn the adjuster in direction
(a) to loosen the clutch cable.
2. Slide the rubber cover and clutch lever free play adjuster back fur-
ther down the clutch cable, and
then loosen the locknut.
3. To increase the clutch lever free play, turn the clutch lever free play
adjusting bolt in direction (a). To decrease the clutch lever free
play, turn the adjusting bolt in di-
rection (b).
4. Tighten the locknut at the clutch cable.
5. Slide the clutch lever free play ad- juster and rubber cover to their
original positions, making sure to
align the slot in the adjuster with
the slot in the adjusting bolt.
1. Clutch lever free play
2. Clutch lever free play adjuster
Clutch lever free play:7.0–12.0 mm (0.28–0.47 in)
2
1 (b)
(a)
1. Locknut
2. Clutch lever free play adjusting bolt
3. Clutch lever free play adjuster
4. Rubber cover
1. Slot
4
3
2
1
(b)
(a)
1
UB4B80E0.book Page 17 Tuesday, March 27, 2018 1:39 PM
Periodic maintenance an d a djustment
7-24
7
EAU23115
Checkin g an d lu bricatin g the
throttle grip an d cab le
The operation of the throttle grip
should be checked before each ride. In
addition, the cable should be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
chart.
The throttle cable is equipped with a
rubber cover. Make sure that the cover
is securely installed. Even though the
cover is installed correctly, it does not
completely protect the cable from wa-
ter entry. Therefore, use care not to
pour water directly onto the cover or
cable when washing the vehicle. If the
cable or cover becomes dirty, wipe
clean with a moist cloth.
EAU23144
Checkin g an d lu bricatin g the
b rake an d clutch levers
The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be lu-
bricated if necessary.
Brake lever
Clutch lever
Recommen ded lu bricants:
Brake lever: Silicone grease
Clutch lever: Lithium-soap-based grease
UB4B80E0.book Page 24 Tuesday, March 27, 2018 1:39 PM
Specifications
9-1
9
Dimensions:
Overall length:1820 mm (71.7 in) (YZ85, YZ85K)
1895 mm (74.6 in) (YZ85LW, YZ85LWK)
Overall width: 760 mm (29.9 in)
Overall height:
1145 mm (45.1 in) (YZ85, YZ85K)
1175 mm (46.3 in) (YZ85LW, YZ85LWK)
Seat height:
840 mm (33.1 in) (YZ85, YZ85K)
870 mm (34.3 in) (YZ85LW, YZ85LWK)
Wheelbase:
1255 mm (49.4 in) (YZ85, YZ85K)
1285 mm (50.6 in) (YZ85LW, YZ85LWK)
Ground clearance: 330 mm (12.99 in) (YZ85, YZ85K)
360 mm (14.17 in) (YZ85LW, YZ85LWK)
Wei ght:
Curb weight:
73 kg (161 lb) (YZ85, YZ85K)
75 kg (165 lb) (YZ85LW, YZ85LWK)
Engine:
Combustion cycle:
2-stroke
Cooling system: Liquid cooled
Number of cylinders:
Single cylinder
Displacement: 85 cm³
Bore × stroke:
47.5 × 47.8 mm (1.87 × 1.88 in)
Compression ratio:
8.2–9.6 : 1
Starting system: Kickstarter
Lubrication system: Premix lubrication
Engine oil:
Engine oil:
YAMALUBE 2R
Recommended brand: YAMALUBE
Transmission oil:
Type:Motor oil SAE 10W-30 type SE or higher or
Gear oil SAE 85W GL-3
Quantity: 0.50 L (0.53 US qt, 0.44 Imp.qt)
Coolant quantity:
Radiator (including all routes): 0.55 L (0.58 US qt, 0.48 Imp.qt)
Air filter:
Air filter element:Wet element
Fuel:
Recommended fuel:
Premium unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity:
5.0 L (1.3 US gal, 1.1 Imp.gal)
Car buretor:
Type × quantity:
PWK28 × 1
Spark plu g(s):
Manufacturer/model:
NGK/BR10EG
Spark plug gap: 0.5–0.6 mm (0.020–0.024 in)
Clutch:
Clutch type:
Wet, multiple-disc
Drivetrain:
Primary reduction ratio:3.611 (65/18)
Final drive:
Chain
Secondary reduction ratio: 3.286 (46/14) (YZ85, YZ85K)
3.643 (51/14) (YZ85LW, YZ85LWK)
Transmission type: Constant mesh 6-speed
Gear ratio: 1st:2.455 (27/11)
2nd: 1.882 (32/17)
3rd:
1.529 (26/17)
4th: 1.294 (22/17)
5th: 1.130 (26/23)
6th:
1.000 (25/25)
Chassis:
Frame type: Semi double cradle
UB4B80E0.book Page 1 Tuesday, March 27, 2018 1:39 PM
11-1
11
Index
A
Air filter element, cleaning .................... 7-10
B
Brake and clutch levers, checking and
lubricating ........................................... 7-24
Brake fluid, changing ............................ 7-21
Brake fluid level, checking .................... 7-20
Brake lever .............................................. 4-2
Brake lever free play, checking............. 7-18
Brake pedal............................................. 4-3
Brake pedal, checking and lubricating ........................................... 7-25
C
Cables, checking and lubricating ......... 7-23
Carburetor, adjusting ............................ 7-12
Care ........................................................ 8-1
Clutch lever ............................................. 4-1
Clutch lever free play, adjusting ........... 7-17
Coolant ................................................... 7-8
D
Drive chain, cleaning and lubricating .... 7-23
Drive chain slack................................... 7-21
E
Engine break-in....................................... 6-3
Engine idling speed .............................. 7-13
Engine serial number ............................ 10-1
Engine, starting a warm .......................... 6-2
Engine stop switch ................................. 4-1
F
Front and rear brake pads, checking.... 7-19
Front fork, adjusting................................ 4-8
Front fork, bleeding .............................. 4-10
Front fork, checking .............................. 7-26
Fuel ......................................................... 4-4
Fuel cock ................................................ 4-6
Fuel tank breather hose .......................... 4-6
Fuel tank cap .......................................... 4-3
H
Handlebar switch .................................... 4-1
I
Identification numbers .......................... 10-1
K
Kickstarter............................................... 4-7
L
Labels, location....................................... 1-1
M
Matte color, caution ................................ 8-1
P
Parking .................................................... 6-5
Part locations .......................................... 3-1 Periodic maintenance and lubrication
chart ..................................................... 7-2
R
Rear suspension, lubricating ................ 7-25
S
Safety information .................................. 2-1
Seat ........................................................ 4-8
Shifting ................................................... 6-2
Shift pedal .............................................. 4-2
Shift pedal, checking ............................ 7-18
Shock absorber assembly, adjusting ... 4-11
Sidestand ............................................. 4-14
Spark plug, checking ............................. 7-6
Specifications ......................................... 9-1
Starter (choke) knob ............................... 4-7
Starting and warming up a cold engine .................................................. 6-1
Steering, checking................................ 7-27
Storage ................................................... 8-3
Supporting the motorcycle................... 7-28
Swingarm pivots, lubricating ................ 7-26
T
Throttle grip and cable, checking and lubricating .......................................... 7-24
Throttle grip free play, adjusting........... 7-13
Tires ...................................................... 7-14
Transmission oil ..................................... 7-7
Troubleshooting ................................... 7-31
Troubleshooting charts ........................ 7-32
V
Vehicle identification number ............... 10-1
W
Wheel bearings, checking .................... 7-27
Wheel (front) ......................................... 7-28
Wheel (rear) .......................................... 7-29
Wheels .................................................. 7-16
Y
YPVS system ........................................ 4-15
UB4B80E0.book Page 1 Tuesday, March 27, 2018 1:39 PM